[CodeQuality] Skip NarrowUnusedSetUpDefinedPropertyRector for property used in nested closure

[TomasVotruba]

Bug

NarrowUnusedSetUpDefinedPropertyRector turns a property only used in setUp()
into a local variable. While doing so it rewrites every $this->property
reference inside setUp() to a bare $property variable — including references
inside nested closures stored for later execution (resolver callbacks, deferred
factories, etc.).

A closure does not capture that local variable (the rule adds no use ($property)
binding), so when the closure runs after setUp() the variable is undefined and
the closure silently returns null.

Found in webonyx/graphql-php
(DeferredFieldsTest), whose rector.php skips this rule. A resolver closure:

$this->categoryDataSource = [/* ... */];
// ...
'resolve' => function () {
    return $this->categoryDataSource; // -> $categoryDataSource (undefined in closure) -> null
}

The rewrite made the deferred resolvers return null, breaking the tests
(verified: 3 failures with zend.assertions=1, gone after the fix, full suite
otherwise unchanged).

Fix

Skip narrowing a property when it is referenced inside a Closure or
ArrowFunction within setUp(). Added skip_property_used_in_closure.php.inc.